I've been using MorPilot replacement batteries since I got my Neato D80 in 2016. Overall I've found the batteries to last around 2 years at our frequency of use (Morpilot batteries only take 1 year). The last one I got in 2018 finally died so it's time to get a new one. Upon receipt I found that the battery connector was DEFECTIVE! I see NO way that this could happen during shipping, even from China. IMHO This should be boxed at the factory on purpose to avoid the stigma of yet another defect. After several attempts I managed to align the required 4 battery connector wires with the contacts on my D80 and the battery eventually charged (several previous misalignments resulted in battery error 0008). Once we have successfully cleaned the house I will return this Revain item as defective.